BIS Monitoring to Detect Deep Sedation

Use of Bispectral Index Monitoring as an Alert to Detect Deep Sedation in Mechanical Ventilated Patients: a Prospective Observational Study

Studies have shown that prolonged deep sedation is associated with adverse clinical outcomes in adult intensive care unit (ICU) patients. The revised guidelines for management of pain, agitation and delirium by the Society of Critical Care Medicine in 2013 also recommended that adult ICU patients should be maintained at a light level of sedation. The key point in light sedation strategy is the assessment of depth of sedation. At present, sedation is monitored mainly by the subjective clinical score systems, such as the Ramsay Scale, the Riker's Sedation-Agitation Scale (SAS) and the Richmond Agitation-Sedation Scale (RASS). However, the subjective and intermittent nature of these scales instruments has limited their application in light sedation algorithm. Consequently, objective and continuous measurement of the level of sedation would be more desirable in clinical practice. In recent years, objective measures of brain function have been of great interests in the evaluation of sedation level, and bispectral index (BIS) has been the most investigated instrument.

Several studies compared BIS with subjective sedation scales in adult ICU patients, and yielded conflicting results. The different approaches to select BIS value may be the most important reason for these inconsistent agreements between BIS and subjective sedation scales. A formal scheme of subjective assessment of the depth of sedation and level of consciousness should incorporate exerting verbal and physical stimuli and observation of the patient's subsequent responses. Our primary aim is to clarify the diagnostic accuracy of BIS in detecting early deep sedation against the reference standard of subjective scale instrument. We hypothesize that BIS monitoring will provide accurate, subjective and continuous evaluation of deepen sedation.

Study Overview

• Status: Completed
• Conditions: Mechanical Ventilation Complication; Disorder; Mental, Sedative; Depressed Level of Consciousness; Psychosis Associated With Intensive Care

• Study Type: Observational
• Enrollment (Actual): 45

Contacts and Locations

Study Locations

• China
  • Beijing
    • Beijing, Beijing, China, 102600
      • Department of Critical Care Medicine, Daxing Teaching Hospital, Capital Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 65 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Adult patients admitted to a 22-bed general ICU in a University Affiliated Hospital will be screened daily and enrolled consecutively.

Description

Inclusion Criteria:

• Adult patients are intubated and ventilated within the previous 24 hours, are administered with continuous or intermittent intravenous sedatives and/or analgesics, and are expected to receive mechanical ventilation and sedation for longer than 24 hours

Exclusion Criteria:

• Age under 18 or over 65 years;
• Continuously infusion of muscle relaxants;
• Diagnosed or suspected brain diseases, which including brain trauma, intracranial hemorrhage, stroke, brain tumors, hypoxic-ischemic encephalopathy, epilepsy and meningitis;
• Diagnosed conditions that resulted in a decrease level of consciousness, which including hypoxemia with partial pressure of oxygen in arterial blood less than 60 mmHg, hypotension with systolic blood pressure less than 90 mmHg, hypoglycemia with blood glucose concentration less than 4.1 mmol/L, anemia with hemoglobin concentration less than 70 g/L, and body temperature below 36 °C.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Light sedation; Light sedation is defined as RASS of +1 to -2.
Deep sedation; Deep sedation is defined as RASS of -3 to -5

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The primary aim of present study is to determine the diagnostic accuracy of BIS monitoring for detecting deep sedation against the reference standard of RASS.	According to RASS evaluation, observations in each time point will be stratified into 2 situations: light sedation (RASS= 0 to -2) and deep sedation (RASS= -3 to -5). Receiver operator characteristic (ROC) curve analysis will be applied to determine the probability of BIS values in predicting deep sedation.	15 minutes before and after RASS evaluation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of deep sedation		24 hours after establishing of BIS monitoring
Occurrence of deep sedation during day- and night-time	Day-time is defined as 8AM to 8PM, and night-time as 8PM to 8AM.	24 hours after establishing of BIS monitoring

Collaborators and Investigators

• Sponsor: Capital Medical University
• Collaborators: Beijing Municipal Health Bureau
• Investigators: Principal Investigator: Jian-Xin Zhou, MD, Capital Medical University

Study record dates

Study Major Dates

• Study Start: August 1, 2014
• Primary Completion (Actual): November 1, 2014
• Study Completion (Actual): December 1, 2014

Study Registration Dates

• First Submitted: July 28, 2014
• First Submitted That Met QC Criteria: July 28, 2014
• First Posted (Estimate): July 29, 2014

Study Record Updates

• Last Update Posted (Estimate): December 30, 2014
• Last Update Submitted That Met QC Criteria: December 24, 2014
• Last Verified: December 1, 2014

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Neurobehavioral Manifestations; Neurocognitive Disorders; Mental Disorders; Consciousness Disorders
• Other Study ID Numbers: KY2014-05--013